By integrating an internal microprocessor

protected from direct sunlight

Key Benefits Direct OEM Replacement: Ensures 100% compatibility with BTH 400A and BTH 500A models

Its multi-tap primary design allows for versatile field integration

Broad Pressure Window: Reliable operation from 5 to 150 PSI

Trane SWT0977 Pressure switch 321702-401 By integrating an internal microprocessorThe Trane SWT0977 Pressure Switch is an essential OEM safety component designed for precise monitoring of combustion blower performance in negative pressure venting systems. This SPNO (Single Pole Normally Open) device, often cross referenced as Honeywell FS4171 1057 or C145526P01, is engineered to ensure the inducer motor is moving sufficient air before allowing the ignition sequence to proceed. Featuring a 1 4 compression connection and a calibrated